This invention relates generally to an improved firearm. In one aspect it relates to a firearm which has reduced recoil action when fired. In another aspect it relates to a firearm which has in increased rate of firing capability.
In what follows the term firearm is intended to refer to both handguns (pistols) and rifles which may be of the semiautomatic or fully automatic type. The term firearm is intended to also comprise fully automatic machine guns. For clarity, the present invention will be described as it relates to applications in semiautomatic handguns. However, the invention may also be adapted to rifles and machine guns.
There are many uses for handguns that include sport, police and military use, and personal self-defense. In the sport known as action or combat shooting, an individual is presented with a series of targets that simulate combat and/or self-defense scenarios. Another type of shooting sport is fixed-target shooting. Police and military personnel also participate in these sports as part of training exercises. In these activities the objective is to hit the target or targets as many times as possible in a given period of time with as high an accuracy as possible. The preferred (and in some sports required by rule) handgun for these activities is of the semiautomatic type wherein each round (bullet) is automatically loaded from a magazine into the gun barrel. However, the trigger must be pulled and released each time the gun is to be fired. In a fully automatic firearm the ammunition is discharged in rapid succession by pulling and holding the trigger only once.
Two important characteristics of semiautomatic handguns are i) minimum recoil, and ii) minimum cycle-time. Other important factors are the gun weight and fire power.
When a gun is fired the explosion of the gunpowder in the ammunition casing or shell creates a forward force on the bullet that propels the bullet out of the gun barrel. Basic physics requires that an equal and opposite force be exerted rearward by the bullet on the gun. This force is referred to as recoil. The portion of the recoil that is sensed by the gun user is referred to as "felt" recoil. The felt recoil is less than the total recoil because automatic and semiautomatic guns contain a spring or springs which absorb some of the energy released when the gun is fired.
Because the gun barrel wherein the recoil force is applied is usually slightly above the wrist of the user, a moment is created about the wrist that tends to rotate the gun barrel upward after firing. In a semiautomatic gun the result is that the gun must be re-aimed before it can be fired again. Excessive recoil can also lead to wrist injury after repeated use. It can be appreciated, therefore, that minimal felt recoil is a desirable attribute for guns since it will reduce the time required to re-aim the gun.
Efforts to reduce felt recoil have resulted in the development of compensators. A compensator is a modification to the gun barrel wherein a small hole is formed in the top of the barrel near the barrel discharge. When the bullet passes the hole a jet of high-pressure gas within the barrel is emitted from the hole. The jet produces a downward force on the end of the gun barrel that counteracts the recoil moment. Compensators have the problem of obscuring the sight of the gun as well as safety problems since the gas jet is hot. Compensators also require a longer barrel that adds weight to the gun.
The cycle-time is the time between successive firings of the gun. In a semiautomatic handgun, for example, the cycle consists of: i) pulling the trigger which fires the bullet, ii) ejection of the empty shell casing from the barrel, and iii) loading of a new round from the magazine (usually in the gun handle) whereby the gun is ready to be fired again. The cycle-time in a semiautomatic handgun is usually faster than the ability of the user to re-aim the gun and fire again. Therefore, the limiting factor in the firing rate is the proficiency of the user.
In a fully automatic gun, such as a machine gun, the limiting factor in the cycle-time is primarily the speed at which the empty shell casing is ejected from the gun and the speed at which a new round can be loaded from the magazine into firing position. The ejection process is controlled by an ejector mechanism that is automatically activated when the gun is fired. The ejector is activated by the gun slide which is a spring-loaded member that is driven rearward by the impact of the explosion of the ammunition. During the rearward motion of the slide, the ejector is activated and ejects the empty shell casing from the gun. Under the action of the slide spring, the slide is first halted and then driven forward returning it to the firing position. At the rear-most position of the slide the magazine is opened and a new round is forced upward (from the magazine in the handle of the gun) into the gun bolt. During the forward motion, the slide rams the round forward into the gun barrel whereby the gun is ready to be fired. The duration of the motion of the slide therefore defines the cycle-time of the gun.
The speed of the slide is primarily a function of its mass. In conventional designs, the force exerted by the gun frame on the slide by for halting its rearward motion is the primary source of felt recoil. In many designs the slide will actually impact upon the frame during the rearward stroke and create a large felt recoil force.